1. Field of the Invention
The invention relates to automatic, premise-monitoring alarm systems such as for example burglary or burglary/fire alarm systems, and more particularly to a system for supervising the integrity of the communication path(s) that carry the alarm message data between a central alarm-message receiving station and a network of remotely-located, automatic, premise-monitoring alarm systems.
2. Prior Art
Premise-monitoring alarm systems monitor a given protected premisexe2x80x94say, for example, a residential home, a jewelry store, a shoe store, a bank vault, or an ATM machine and the likexe2x80x94for the occurrence of a given alarm event:xe2x80x94e.g., an unwanted intrusion, unauthorized entry or smoke and so on. Some alarm events simply correspond to a xe2x80x9clow batteryxe2x80x9d condition in the protected-premise control unit or panel. Upon detection of a given alarm event, the automatic alarm system signals the alarm event to a central alarm-monitoring station. The central alarm-monitoring station, which may be a public or private service, may manually process the signal by an attendant who can dispatch police or fire-fighters or alert the store-owners or take whatever other steps are appropriate. Prior art automatic alarm systems have typically operated over standard voice-grade telephone lines.
It has been a problem that if the telephone line is cut or otherwise drops out of service, then the protected premise is isolated from the central alarm monitoring station, and is without means to even signal the loss of the telephone line. Indeed the central alarm monitoring station greatly desires a signal that corresponds to or indicates the loss of the telephone link between itself and the protected premise, as that is an alarm event in itself.
There are prior art systems which address this problem of loss of telephone service (or a communication link) between the protected premise and the central alarm monitoring station. As will be described further below, the prior art systems incorporate various techniques for supervising the integrity of the telephone (or communication) link. There are also, however, various shortcomings associated with the prior art systems as will also be described below. Accordingly, it is an object of the invention to overcome the shortcomings of the prior art and provide improved, communication path integrity supervision in a network system for automatic alarm data communication.
These and other aspects and objects are provided according to the invention in a communication path integrity supervision system in a network system for automatic alarm data communication. In accordance with one format of the invention, the integrity supervision system comprises the following. There is a xe2x80x9ccheck-in messagexe2x80x9d receiving center which is provided with computer memory for storing check-in schedules. There is a network of diverse communication paths linked to the center. And there are also a plurality of remote, automatic alarm-data communicators that are communicative with the center over the diverse paths.
Each remote communicator is given means for generating and sending successive xe2x80x9cnext promised check-inxe2x80x9d messages, on schedule as promised. The center responds to the reception of each such message by updating the memory, scheduling or rescheduling the next promised check-in for that remote communicator. The center is further configured with alerting means for alerting instances when any remote communicator fails to meet its scheduled or rescheduled next promised check-in.
These remote communicators are characteristic of a protected-premise alarm panel and are combined with circuitry including alarm-event sensors for generating data responsive to detection of alarm events. Each remote communicator includes means for encoding the xe2x80x9cnext promised check-inxe2x80x9d message with a time factor that corresponds to the timeliness of the reception due for the next promised check-in for that communicator. Underlying the communication between the center and the remote communicators is a protocol shared by them as regards the time factor. That is, the protocol recognizes both (i) a set of values signifying intervals of time as well as (ii) a null factor signifying that the sending communicator wishes to check or sign off from the system. Hence the alerting means will no longer apply or act on failures to timely respond in reference to that particular communicator.
The alerting means responds to instances when any remote communicator fails to meet its scheduled or rescheduled next promised check-in, by producing an alert signal, which may be acted on by an attendant of the message receiving station
The diverse communication paths can be alternatively any of the following:xe2x80x94eg., they can comprise a substantially homogenous network of cables (either conductors or fiber optic), or a substantially homogenous network of radio links, or a conglomerate network including both cables and radio links. Also, the memory for the check-in message receiving center preferably is configured with a table data structure for tabulating communicators against their next promised check-in schedule.
Another format of the invention might comprise the following aspects. It might have a network of communication paths as before, as well as a plurality of remote, automatic alarm data communicators linked to the network. There then might be at least one monitoring station communicative with the remote communicators over the network.
Each remote communicator would have means for dispatching successive xe2x80x9cnext check-inxe2x80x9d messages, including timing means for timing the timeliness of the dispatch of each succeeding xe2x80x9cnext check-inxe2x80x9d message. The at least one monitoring station would have memory and would also respond to reception of each such message by setting or resetting in the memory an appointed xe2x80x9cnext check-inxe2x80x9d time for that remote communicator. Moreover, the at least one monitoring station would have a monitoring means for monitoring the appointed next check-in times in the memory for instances of failure to receive from any remote communicator a timely succeeding xe2x80x9cnext check-inxe2x80x9d message.
Each remote communicator includes means for encoding the xe2x80x9cnext check-inxe2x80x9d message with a time factor that allows monitoring for the appointed time by which reception is due for the succeeding next check-in from that communicator. The timing means is configured to dispatch each succeeding xe2x80x9cnext check-inxe2x80x9d message about a minute before such lapse of the interval of time that was signified by the preceding xe2x80x9cnext check-inxe2x80x9d message.
In accordance with an alternative format of the invention (wherein the formats presented here are exemplary only and not an exhaustive depletion of all the formats possible in accordance with this disclosure), a communication path integrity supervision system in a network system for automatic alarm data communication might comprise these next aspects. That is, as before it includes a network of communication paths. There are also a plurality of automatic alarm data transmitters linked to the network. And there is at least one receiver on the network for receiving the automatic alarm data.
Each transmitter includes a xe2x80x9ccheck-inxe2x80x9d means for generating and sending discrete series of xe2x80x9ccheck-inxe2x80x9d messages chosen from a group including:
a first message for any such series,
a last message of such series, and
at least zero intermediate messages bracketed therebetween.
Wherein, each xe2x80x9ccheck-inxe2x80x9d message is encoded with a time parameter which expresses a timeliness factor for the""succeeding message in the series. The receiver has computer memory and it also responds to reception of any first check-in message from a given transmitter by storing in memory the time parameter therefor. The receiver responds to any timely received intermediate message by updating in memory the new time parameter therefor. The receiver further has a monitoring function for monitoring the stored check-in parameters given only by first and intermediate check-in messages from any transmitter for instances of failure to receive from such transmitter a timely succeeding xe2x80x9ccheck-inxe2x80x9d message.
On the other hand, the receiver responds to reception of any last message in a series from a given transmitter by nullifying the monitoring function as applied to that given transmitter, until the reception of a next first check-in message from that given transmitter after a period of dormancy.
The check-in means is configured to send each succeeding intermediate or last xe2x80x9ccheck-inxe2x80x9d message about a minute before expiration of the timeliness factor for that succeeding xe2x80x9ccheck-inxe2x80x9d message. The check-in means also allows configuration with plural modes for choosing and assigning a time parameter to encode in each first or succeeding intermediate xe2x80x9ccheck-inxe2x80x9d message. In accordance with one such one mode, it causes assignment of time parameter corresponding to regularly spaced time intervals. And in accordance with the other such mode, it causes assignment of randomly chosen time intervals ranging between a value greater than zero and a larger value which is finite. In a preferred embodiment, this translates to values between two (2) and sixty (60) minutes.
Additional aspects and objects of the invention will be apparent in connection with the discussion further below of preferred embodiments and examples.